Laser cladding technology: a new process method for substrate surface coating Laser cladding technology is a process that places filler materials on the surface of the substrate and melts them with the substrate surface through laser irradiation to form a surface coating. This surface coating can significantly improve the properties of the base material, such as wear resistance, corrosion resistance, heat resistance, oxidation resistance, and electrical properties. Laser cladding technology has the advantages of high economic benefits, cost reduction, and saving of rare materials, so it is widely used in industrial manufacturing. Characteristics of laser cladding technology has the following characteristics: 1. Rapid solidification process: The cooling rate of laser cladding technology is fast (up to 106K/s), which makes it possible to obtain fine-grained structures or produce equilibrium states that cannot be obtained New phases, such as unstable phase, amorphous state, etc. 2. Low dilution rate: The coating dilution rate of laser cladding technology is low (generally less than 5%), which can form a strong metallurgical bond or interface diffusion bond with the substrate. By adjusting the laser process parameters, a good coating with a low dilution rate can be obtained, and the coating composition and dilution can be controlled.3. Small heat input and distortion: The heat input and distortion of laser cladding technology are small, especially when high power density and rapid cladding are used, the deformation can be reduced to the assembly tolerance of the part. 4. High selectivity: There are almost no restrictions on powder selection for laser cladding technology, especially for depositing high-melting-point alloys on the surface of low-melting-point metals. It can perform selective deposition, consumes less material, and has an excellent performance-price ratio. 5. Wide thickness range: The thickness range of the cladding layer of laser cladding technology is wide, and the thickness of one coating with single-pass powder feeding is 0.2~2.0mm. 6. Easy to realize automatic control: The beam aiming of laser cladding technology can make inaccessible areas clad. The process is easy to automate and is very suitable for the wear and repair of common wearing parts in the oil field. The application of laser cladding technology is widely used in aerospace, automobile manufacturing, mold manufacturing, petrochemical, and other fields. In the aerospace field, laser cladding technology can create high-performance coatings to improve the wear resistance and corrosion protection of components. In the field of automobile manufacturing, laser cladding technology can create highly wear-resistant coatings to extend the service life of engine components.

In the field of mold manufacturing, laser cladding technology can produce coatings with high surface hardness and low friction coefficient to extend the service life of the mold. In the petrochemical industry, laser cladding technology can produce coatings with high corrosion resistance and high-temperature oxidation resistance to extend the service life of the equipment. Similarities and Differences between Laser Cladding and Laser Alloying Laser cladding and laser alloying both use laser technology to improve the properties of materials. But there are some differences between them. Laser cladding forms a thin coating on the surface of the material to improve the properties of the material, while laser alloying forms an alloy layer inside the material to improve the strength and toughness of the material. In addition, the coating thickness of laser cladding is generally between 0.2~2.0mm, while the alloy layer thickness of laser alloying is generally between 0.1~2.0mm. Summary Laser cladding technology is a new technology with high economic benefits. It can prepare high-performance alloy surfaces on cheap metal substrates without affecting the properties of the substrate, reducing costs and saving precious and rare metal materials.

It has the characteristics of a rapid solidification process, low dilution rate, small heat input and distortion, high selectivity, wide thickness range, and easy automatic control. Therefore, it is widely used in aerospace, automobile manufacturing, mold manufacturing, petrochemical, and other fields. Although laser cladding technology and laser alloying technology both use laser technology to improve the properties of materials, there are some differences between them. Laser cladding technology forms a thin coating on the surface of the material, while laser alloying forms an alloy layer inside the material. Therefore, the application prospects of laser cladding technology are very broad, but at the same time, further research and development are needed. In future research, we should explore more application fields while further improving the efficiency and quality of laser cladding technology to meet the needs of industrial manufacturing. Laser cladding and laser alloying use high-energy-density laser beams for rapid melting to form alloy coatings with different compositions and properties. Although the two processes are similar, there are essential differences. During the laser cladding process, the cladding material is completely melted, and the base melted layer is very thin, which has little impact on the composition of the cladding layer; while laser alloying adds alloy elements to the surface melting cladding of the base material to form a base material-based cladding layer. new alloy layer.

Laser cladding technology is of great significance in repairing failed parts and directly manufacturing metal parts, and has received great attention from the global scientific community and enterprises. Evaluating the quality of laser cladding layers mainly considers two aspects: macroscopic and microscopic. From a macro perspective, it is necessary to examine indicators such as the shape of the cladding channel, surface flatness, cracks, pores, and dilution rate; from a micro perspective, it is necessary to examine the structure formation and the ability to provide the required performance. In addition, it is also necessary to determine the types and distribution of chemical elements in the cladding layer, analyze the metallurgical bonding of the transition layer, and conduct necessary quality life testing. The focus of research work includes the research and development of cladding equipment, molten pool dynamics, alloy composition design, crack formation, and control methods, and the bonding force between the cladding layer and the substrate. However, laser cladding technology faces some major problems in its further application. First of all, the main reason why it has not yet achieved complete industrialization is the instability of the quality of the cladding layer. During the laser cladding process, the heating and cooling speeds are extremely fast, up to 1012°C/s. Due to the difference in temperature gradient and thermal expansion coefficient between the cladding layer and the base material, various defects such as pores, cracks, deformation, and surface unevenness may occur.

Secondly, the detection and implementation of automated control of the laser cladding process is also a challenge. In order to solve these problems, research and development need to be strengthened. First of all, efforts should be made to improve cladding equipment and improve the stability and control capabilities of the cladding process. Secondly, it is necessary to study the dynamics of the molten pool in-depth and understand the temperature and material flow rules during the cladding process to optimize the formation of the cladding layer. In addition, the design of alloy components is also key. By rationally selecting alloy elements and proportions, the structure and properties of the cladding layer can be controlled. At the same time, the formation, expansion, and control methods of cracks should be studied to reduce the occurrence of defects. Finally, it is necessary to strengthen the research on the bonding force between the cladding layer and the substrate to improve the wear resistance and bonding strength of the cladding layer. In summary, laser cladding and laser alloying are technologies that use laser beams to achieve rapid melting and form alloy coatings. Although the two processes are similar, there are fundamental differences in the way and purpose of melting materials. Laser cladding technology is of great significance in repairing failed parts and directly manufacturing metal parts, and has received global attention. However, this technology faces unstable cladding layer quality and automatic control problems in industrial applications.

In order to solve these problems, research and development should be strengthened, cladding equipment should be improved, molten pool dynamics should be studied in depth, alloy composition design should be optimized, crack formation should be controlled, and the bonding force between the cladding layer and the substrate should be strengthened. Future research should focus on solving these problems and promote the application of laser cladding technology in the field of material preparation and manufacturing. What problems do you think laser cladding technology will encounter in future development? Problems in laser cladding technology in engineering applications and Industrialization Laser cladding technology is widely used in the machinery manufacturing industry, but its cracking sensitivity is still a problem. Although the formation and propagation of cracks have been studied, the control methods are not yet mature. This article will introduce the application, scope of application, and several typical applications of laser cladding technology. Application of laser cladding technology Laser cladding technology has a very wide scope and application fields. It has been successfully carried out on cobalt-based, nickel-based surfaces of stainless steel, mold steel, malleable cast iron, gray cast iron, copper alloy, titanium alloy, aluminum alloy, and special alloys. Laser cladding of self-fluxing alloy powders and ceramic phases such as base and iron base.

Among them, laser cladding iron-based alloy powder is suitable for parts requiring local wear resistance and easy deformation; nickel-based alloy powder is suitable for components requiring local wear resistance, hot corrosion resistance and thermal fatigue resistance; cobalt-based alloy powder is suitable for parts requiring local wear resistance, thermal corrosion resistance and thermal fatigue resistance; Wear, corrosion resistance and thermal fatigue resistance parts; ceramic coatings have high strength at high temperatures, good thermal stability, and high chemical stability, and are suitable for parts requiring wear resistance, corrosion resistance, high temperature resistance, and oxidation resistance. . Several typical applications of laser cladding technology 1. Manufacturing and remanufacturing of mining equipment and its parts. Coal mining equipment is used in large quantities in mines, wears out quickly, and parts are damaged relatively quickly. However, laser manufacturing and remanufacturing technology can Used to repair these damaged parts. Among them, coal machine equipment parts include shearers, tunnel boring machines, scraper conveyors and hydraulic supports. These parts require local wear resistance, and laser cladding technology can meet this demand. 2. Manufacturing and remanufacturing of power equipment and its parts. Power equipment is distributed in large quantities and operates continuously, and its parts have a high probability of damage. Due to the special working conditions of core equipment such as steam turbines and gas turbines, damaged unit parts need to be repaired regularly every year.

Laser remanufacturing technology can be used to repair damage to the main shaft diameter, moving blades and other parts to restore serviceability, and the cost of this process is only 1/10 of the price of a new unit. In addition, laser cladding of the motor rotor shaft is also an effective repair method. Development Prospects of Laser Cladding Technology The difficulties in the engineering application and industrialization of laser cladding technology mainly come from the control of cracking sensitivity. However, with the continuous development of laser cladding technology, related technical bottlenecks are expected to be broken through. In the future, laser cladding technology is expected to be applied in a wider range of fields, such as high-end equipment manufacturing and new energy fields. Therefore, we need to continue to strengthen research on laser cladding technology and improve the quality and efficiency of its application. Conclusion Laser cladding technology is widely used in the machinery manufacturing industry, but its cracking sensitivity is still a problem. This article introduces the application, scope of application and several typical applications of laser cladding technology, and discusses the development prospects of laser cladding technology. In the future, we should continue to strengthen research on laser cladding technology and strive to overcome its technical difficulties to meet a wider range of application needs. What other issues do you think are worth studying and solving in the future development of laser cladding technology?

Remanufacturing of key components of equipment in the petroleum, railway and other machinery industries Equipment in the modern petrochemical industry, railway transportation and other machinery manufacturing industries basically adopt a continuous mass production model. During the production process, machines work in harsh environments for long periods of time, causing damage, corrosion, wear and other problems to components within the equipment. These components are usually very expensive, involve many types, and are mostly complex in shape, making them difficult to repair. However, with the emergence of laser cladding technology, these problems are no longer difficult to solve. For equipment in the petrochemical industry, frequently problematic components include valves, pumps, impellers, large rotor journals, discs, bushings, bearing bushes, etc. Laser cladding technology can be applied to the manufacturing and remanufacturing of these components, such as laser cladding of hard ceramic coatings such as oil drill pipes and drilling tools, which can greatly extend the service life of parts. In the field of railway transportation, the demand for new railway vehicles is very large, and the quantity and performance requirements for main components are also increasing. Remanufacturing technology can be applied to the remanufacturing of vehicle wear parts.

Laser surface strengthening is the core technology and process method of remanufacturing. Laser surface cladding technology can be applied to repair and strengthen the surface of remanufactured parts, such as laser cladding of high wear-resistant steelmaking continuous casting rollers. In addition to the petrochemical industry and railway transportation, the remanufacturing of key components in other machinery manufacturing industries is also very important. This involves industries such as metallurgy, mining, chemical industry, aviation, automobiles, ships and machine tools. Laser cladding processing technology can be used to repair and optimize the performance of precision equipment, large equipment, and valuable parts in these fields where they are worn, eroded, and corroded. Laser cladding technology has broad application prospects in manufacturing and remanufacturing key components. It can not only extend the service life of parts, but also improve their performance and reduce resource waste and environmental pollution. Therefore, in the process of promoting and applying laser cladding technology, we need to pay more attention to technology promotion and talent training to respond to market demand and improve the core competitiveness of my country’s industrial manufacturing. In short, laser cladding technology has become an important means of modern industrial manufacturing and remanufacturing of key components. We need to continue to explore and innovate to adapt to market needs and development trends.

At the same time, we also need to pay more attention to environmental protection and resource reuse, making laser cladding technology an important tool for achieving sustainable development. What do you think are the highlights and shortcomings of the application of laser cladding technology in manufacturing and remanufacturing key components? What suggestions do you have?